Electrical musical instrument



Feb. 25, 1936. L. E. A. BOURN ELECTRICAL MUSICAL INSTRUMENT Filed Jan.31, 1935 e Sheets-Sheet 1 Feb. 25, 1936. I L. E. A. BOURN 2,032,044

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ELECTRICAL MUSICAL INSTRUMENT Filed Jan. 31, 1935 6 Sheets-Sheet 347/197704 lisurfblmvflzamlwzaiaamv @4.

Feb. 25, 1936. E. A. BOURN 2,032,044

ELECTRICAL MUSICAL INSTRUMENT Filed Jan. 31, 1935 6 Sheets-Sheet 4 jFighi.

Feb. 25, 1936. L. E. A. BOURN 2,032,944

ELECTRICAL MUSICAL INSTRUMENT Filed Jan. 31, 1935 6 Sheets-Sheet 5 L. E.A. BOURN ELECTRICAL MUSICAL INSTRUMENT Feb. 25, 1936,

Filed Jan. 31, 1935 6 Sheets-Sheet 6 Patented Feb. 1936 UNITED STATESPATENT OFFICE ELECTRICAL MUSICAL INSTRUMENT Application January 31,1935, Serial No. 4,242 In Great Britain February 8, 1934 15 Claims.

This invention relates to electrical musical instruments and refers moreparticularly to electrical musical instruments in which each note isproduced by an undulating electrical potential generated by the relativerotation of two parts one of which carries a wave or undulating form andthe other a scanning form for scanning said wave form.

The object of the invention is the provision of means for compensatingfor constructional inaccuracies in connection with said two parts, andthe invention consists broadly in the arrangement that both the wave orundulating form and the scanning form are repeated at intervals 15wholly or partly around a circle about the axis of relative rotation,the distance apart of the wave forms and that of the scanning form'sbeing equal or one being a multiple of the other.

In order that the invention may be more clearly understood, certainapparatus in accordance therewith will now be described, reference beingmade to the accompanying drawings wherein:-

Figure 1 is a plan of a single primary element for use in an apparatusfor producing undulating potentials by electrostatic induction, forgenerating notes in an organ operating on the principle disclosed in myprior specification Serial Number 712,724, Patent No. 1,996,669 of April2, 1935, said single primary element being adapted to generate one note.

Figure 2 is a plan of that portion of a secondary element, common to aset of such primary elements, which is adapted to immediately overliesaid single primary element.

Figure 3 is a plan, partly broken away and with the elements in thespace a: being omitted for the sake of clearness, of one of the sets ofpri- 40 mary elements.

Figure 4 is a similar plan of the whole secondary element adapted tooverlie said set, the part of said secondary element covering the spaceJ being omitted for the sake of clearness.

Fig. 5 is a sectional side elevation illustrating a set of primaryelements and a set of secondary elements in assembled relation.

Fig. 6 illustrates a modified form of secondary element.

50 Fig. 7 illustrates another modified form of secondary element.

Fig. 8 illustrates another modified form of secondary element.

Fig. 9 illustrates another modified form of secondary element.

Fig. 10 illustrates a modified form of primary element.

Fig. 11 illustrates another modified form of primary element.

Fig. 12, which is identical with Fig. 1 of my Reissue Patent No. 19,702,dated September 17, 1935, is a fundamental diagram of connectionsillustrating the manner of generation of each individual partial note.

Fig. 13, which is identical with Fig. 2 of said reissue patent,illustrates the correlation between the generators for six octaves of agiven note (together with their partials) and the six corresponding keysof the key board. For the sake of simplicity the number of primaryelements in the set shown in this figure is reduced from that shown inFig. 3.

Fig. 14, which is identical with Fig. 3 of said reissue patent,illustrates the operation of the stops for predetermining the quality ofthe notes.

In my said Patent No. 1,996,669 an arrangement is disclosed in which theundulating potential for producing each note is generated by means of agenerator consisting of a ring of conducting material having anundulating form and a scanning electrode which revolves about the axisof said ring keeping close thereto. When the undulating ring isconnected to a source of potential, an undulating potential will beelectrostatically induced on the scanning electrode of a frequencydepending on the speed of rotation of said electrode and the distanceapart of the undulation of the ring. This undulating potential isapplied through a common amplifier to a loud speaker and a musical note,whose pitch depends on said frequency is accordingly produced.

For said prior arrangement the undulating rings required for the wholeinstrument are arranged in a number of identical sets, the rings of eachset being co-planar and concentric with one another, being mounted on acommon insulating disc. A common scanning electrode serves for each set,said electrode taking the form of a radial arm rotating about the axisof the set and passing close to the surface of all the rings. By asystem of stops and keys the required undulating rings are connected tothe source of potential and the required notes are accordingly producedby the loud speaker.

It has, however, been found exceedingly difiicult in practice to freethe output from variations and irregularities due to constructionalinaccuracy. For example if the axis of rotation of the scanningelectrode should be slightly out of line with the axis of the undulatingrings the electrode will pass slightly closer to the surface of therings on one side than on the other and the notes produced willaccordingly have an undesirable rise and fall of intensity. The samething will occur if the disc on which the undulating rings are mountedshould be slightly out of plane. Again if there should be any slightinaccuracy in the wave form of a ring at any part of its circumferencethis will produce a corresponding variation in the note produced.

In accordance with the apparatus now to be described with reference tothe accompanying drawin Figure 1.

ings, these and other constructional inaccuracies are compensated for byconstructing the scanning element with a portion proper to, and adaptedto overlie, each primary element or undulating ring, said portioncarrying a scanning form which is repeated at intervals equal to thewave length of the primary element which it overlies, so that as saidscanning element rotates, the scanning forms of such portion arealternately in phase and out oi phase with the wave forms of the primaryelement which it overlies at a frequency depending on the distance apartof the wave forms of said primary element and the speed of rotation.Thus in Figure 1, the reference l designates an individual primaryelement or undulating ring and in a Figure 2 the reference 2 designatesthe portion of the scanning element which is proper to, and adapted tooverlie the primary element illustrated The said portion 2 of thescanning element comprises a number of short radial scanning forms ormember 21:. extending between ring supports 2b. These short radialscanning members 2a are spaced apart by a distance equal to the Wavelength of the primary element i and the ring supports 21) have radiirespectively just greater than the maximum, and just less than .theminimum, radii of the primary element i.

As in the disclosures of the prior patent aforesaid the individualprimary elements l are arranged in concentric sets each of which setscomprises the primary elements for all the octaves of one note togetherwith the partials thereof, so that there are in all twelve sets ofprimary elements for the complete musical scale. Also as in said priorpatent a common scanning electrode is employed for each set of primaryelement. One of said sets of primary elements is shown in Figure 3 andit will thus be seen that in the present arrangement the common scanningelectrode takes the form, as shown in Figure 4 of a grid consisting of anumber of concentric ring supports 2b which are superimposed over therespective spaces between the undulating rings l and a set of shortradial scanning members 2a extending between each adjacent pair of theseconcentric rings, the short radial scanning member 2a of each set lyingtransversely over a respective undulating ring l and thesescanningmembers being spaced as stated by a distance equal to the wavelength of this ring.

It is clear that if any undulating ring 5 is ener= gized an undulatingpotential will be electrostatically induced on the common scanningelectrode by virtue of said ring being scanned by the set of scanningmembers 2a .which lie over it; and as these scanning members are spacedapart a distance equal to the wave length of this ring, all of them willbe at the same position relative to a wave formation at any given momentand the inaccuracies such as those above referred to will not have anyresultant efiect on the potential induced on the common scanningelectrode. Thus if the scanning members 2a are slightly closer to thering I on one side than the other this will not affect the mean distanceof all of said scanning members from the undulating ring. Again ifcertain of the wave forms of a ring varies slightly from others thiswill not produce any irregularity in the potential induced in the commonscanning electrode as each wave form is continuously being scanned andnever ceases to be operative. The concentric rings 2b of the commonscanning electrode between which the scanning members 2a extend willequally have no eflect on the induced potential, and the out of phasescanning members 2a which do not lie immediately above the undulatingrings l under consideration are also without substantial effect on thepotential induced by said undulating ring.

In practice the undulating rings l are formed by first providing theinsulating disc 3 with a coating of graphite, then dividing this coatinginto rings by means of longitudinal sine wave cuts a of the requiredwave length. Each ring I is constituted as shown by the graphite stripbetween two of said cuts a of the same wave length and in phase with oneanother. The graphite strips 6 located between the rings 1! are renderedinefiective by being earthed.

The concentric rings 2b and radial scanning members 2a of the gridelectrode are formed of graphite located in channels engraved upon adisc 5 of insulating material. Thus the circular and radial channels ofthe required grid form having been engraved on the disc 5, the graphiteis first coated over the whole disc after which the surface is rubbeddown for removal of all the graphite except what is lodged in thechannels.

It will be appreciated that although the fullest compensation isobtained by a complete set of the short radial scanning members 2a foreach undulating ring I as described, a measure of compensation will beobtained by less than complete set of such scanning members 2a. Forexample, a high degree of compensation will be obtained by providinghalf the number of scanning members 20. spaced apart by a distance equalto twice the wave length of the corresponding ring as shown in Fig. 6.Indeed a considerable measure of compensation will be effected byproviding only two scanning members 2a for each undulating ring I,located diametrically opposite to each other as shown in Fig. 7. Again,in some cases it might be preferred to arrange the scanning members 2afor each undulating ring I in two diametrically opposite groups as shownin Fig. 8, those of each group being spaced apart by a distance equal tothe wave length, or in two pairs of diametrically opposite groups asshown in Fig. 9, the essential in every case being that the scanningmembers are in phase with the wave forms of the ring being scanned.

In like manner, where a complete set of scanning members 211 areemployed for each undulating ring l, less than a complete set ofundulations could be employed. Thus in Fig. 10 a ring I is shown havingonly two diametrically opposite undulations. In theory a singleundulation would be sumcient if a complete set of scanning members 2awere provided but in practice this would produce variations similar tothose produced when only one scanning member is employed for aosaourangement would thus not come within the scope of the present invention.

In the arrangement of said prior patent each primary element Iconstitutes a complete ring and a number of rings of identical wavelength are included in each set for the different partials of differentoctaves which are of the same pitch. This arrangement is usuallypreferred, but in ac cordance with the present invention it may bevaried by employing a complete grid having a complete set of radialscanning members M for each undulating ring as in Figure 4, and dividingeach undulating ring into twice as many insulated arcuate portions asthere are partials requiring the frequency of said ring, and eachprimary element may be constituted by an electrically connected oppositepair of such arcuate portions, so that compensation for structuralinaccuracy will be afforded as heretofore described.

In this way considerable economy of space will be effected, as all theprimaries of identical wave length will be constituted by mutuallyinsulated arcuate portions of the same ring. Thus Fig. 11 shows a singlering of the same wave length as that of Fig. 1 which has been divided inthe man'- ner described so as to constitute two separate primaryelements each having the same wave length, this being on the assumptionthat there are two partials of different octaves which are of the pitchrepresented by said wave length. As shown this ring comprises twodiametrically opposite pairs of arcuate undulating portions, theportions of each pair being electrically connected together andinsulated from those of the other.

It will be appreciated that the system of keys, stops and bus bars isthe same as in the prior specification aforesaid. Thus referring to Fig.12, which is identical with Fig. 1 of my Reissue Patent No. 19,702,dated September 1'7, 1935, each whole secondary element, representeddiagrammatically at x, is connected to a common amplifier 6 whichsupplies a loud speaker I and when one of the undulating rings I ininductive relation to said secondary element is connected to a source ofpotential an undulating potential will be electrostatically induced onsaid secondary element of a frequency depending on the speed of rotationof said secondary element and the distance apart of the undulations ofthe ring I.

This undulating potential will be applied to the.

amplifier 6 and a musical note, whose pitch depends on the saidfrequency and whose intensity depends on the potential to which the ringwas raised, will be emitted from the loud speaker 1.

The source of potential may be any suitable source and the connection ofsaid ring I to said source is through the medium of a bus bar 8 adaptedto be connected to the ring I by means of a contact 9 on a key I andadapted to be connected to said source by means of a contact I I on astop I2.

In the arrangement being described by way of example we will supposethere are seventy-two keys, that is to say the keys for six octaves ofeach of the twelve notes of the tempered scale. Each of the octaves inthe arrangement being described is capable of being produced with eightpartials though in practice this number would probably be increased.

In practice the rings I for the partials of all six octaves of each noteare included in one set so that there are in all twelve sets of rings Ieach set having associated with it six keys I0. One such set of rings Itogether with the associated six keys I II is illustrated in Fig. 13,which is identical with Fig. 2 of my reissue patent aforesaid.

In practice each set of generators is made identical and the wholetempered musical scale is covered by rotating the successive secondaryelements of each set at a speed of 12 /2 times that of the preceding.

Each of the six keys I0 associated with each set of rings is providedwith eight contacts 9 for the eight partials of the octave representedby that particular key, each contact 9 being connected to theappropriate ring as illustrated in Figure 12.

Eight of the bus bars 8 are provided which are common throughout thewhole scale and it will be seen from Figure 12 that when any key I0 isdepressed all of its contacts 9 will be connected to respective busbars, the first to the first bus bar, the second to the second bus barand so on.

Thus the note appertaining to that key will be produced in a qualitywhich depends upon which of the eight bus bars are energized.

The energization of the bus bars is controlled by the stops i2. Each ofthe stops I2 has a number of contacts II each connected to the source ofpotential, which contacts II when the stop is drawn, engage with, andeffect energization of, selected ones of the bus bars 8 according to thequality of notes which it is required to be produced by the keys. A stopI2 is illustrated by way of example in Figure 14, which is identicalwith Fig. 3 of my reissue patent aforesaid, which upon depressioneflects energization of the first, third and seventh of the bus bars 8so that when this stop is drawn the subsequent depression of each keyIII will sound the first, third and seventh partial of the noteappertaining to that key.

Each bus bar 8 is permanently connected to earth through a resistance I3of say 100,000 ohms and its connection to the source of potential byeach contact II is through an independent path including a resistance I5of the same order. Thus when the bus bar 8 is energized through twodifferent contacts I I simultaneously, owing to two different stops I2being simultaneously actuated,

its potential will be higher than if it were energized through only oneof said contacts and thus the correct additive effect will be obtained.

Each contact 9 is connected to its proper ring I through an adjustableresistance I6 and a leak 20 of say 20 megohms in series, a leak 2i ofsay 5 megohms extending to earth from a point between said resistance I6and leak 20, and a condenser I8 being connected between the earth andthe ring I.

Fig. 5 illustrates the structional details of one of the generator unitsshowing the rings I mounted on the insulating disc 3, and the secondaryelement mounted on the disc 5 rotatable about the common axis of the twodiscs. As shown said d'sc 5 is mounted on a spindle 22 carrying adriving pulley 23.

What I claim and desire to secure by Letters Patent is:-

1. In an electrical musical instrument, an electrostatic generatoradapted to electrostatically induce a varying potential for producing asingle individual sound tone, comprising two relatively rotatableelectrodes in electrostatically inductive relation, one of whichconstitutes a plurality of wave forms and the other a plurality ofscanning forms therefor, both said wave and scanning forms beingrepeated about the axis of relative rotation at such intervals that, atany given moment, the wave and scanning forms of every constitutes aplurality of wave forms, and a pluinductively cooperating pair are atthe same re tion.

2. In an electrical musical instrument, an elec trostatic generatoradapted to electrostatically induce a varying potential for producing asingle individual sound tone, comprising two relatively rotatableelectrodes axially spaced and at a substantially common radius so as tobe in electrostatically inductive relation, one of which constitutes aplurality of wave forms and the other a plurality of scanning formstherefor, both said wave and scanning forms being repeated about theaxis of relative rotation at such intervals that at any given moment,the wave and scanning forms of every inductively cooperating pair are atthe same relation.

3. In an electrical musical instrument, an electrostatic generatoradapted to elecn'ostatically induce a varying potential for producing asingle individual sound tone, comprising two relatively rotatableelectrodes in electrostatically inductive relation, one of which isconstituted by a ring of undulating form concentric with the axis ofrelative rotation and the other of which comprises a plurality ofscanning members arranged so as to scan said ring as relative rotationtakes place, said scanning members and the undulations of the ring beingat such intervals that, at any given moment, the undulation and thescanning member of every inductively cooperating pair are at the samerelation.

4.. In an electrical musical instrument, an electrostatic generatoradapted to electrostatically induce a varying potential for producing asingle individual sound tone, comprising two relatively rotatableelectrodes in electrostatically inductive relation, one of which isconstituted by a ring of undulating form concentric with the axis ofrelative rotation and the other of which comprises a plurality ofscanning members spaced axially from, and at substantially the sameradius as, said ring so as to be adapted to'scan said ring as relativerotation takes place, said scanning members and the undulations of thering being at such intervals that, at any given moment, the undulationand-the scanning member of every inductively cooperating pair are at thesame relation.

5. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts, a plurality of electrodes carried by one of said parts, each ofwhich electrodes constitutes a plurality of wave forms, and a pluralityof sets of electrically connected scanning forms carried by the otherpart for scanning the respective wave form electrodes in inductiverelation therewith, both the wave and scanning forms of each inductivelycooperating wave form electrode and scanning form set being repeatedabout the axis of relative rotation at such intervals that, at any givenmoment, the wave form and scanning form of every inductive lycooperating pair are at the same relation.

6. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts, a plurality of elec trodes carried by one of said parts in acommon plane at right angles to the axis of relative rotation and atdiilerent radii with respect to said axis of relative rotation, each ofwhich electrodes rality of sets of electrically connected scanningforms, for the respective wave form electrodes, carried by the otherpart in another common plane at right angles to said axis of relativerotation and at substantially the same radii as the respective wave formelectrodes so as to be adapted to scan the same in electrostaticallyinductive relation, both the wave and scanning forms 01 each inductivelycooperating wave form electrode and scanning form set being repeatedabout the axis of relative rotation at such intervals that, at any givenmoment, the wave form and scanning form of every inductively cooperatingpair are at the same relation.

'7. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts, a plurality of rings of undulating form carried by one of saidparts concentric with the axis of relative rotation and at difierentradii in a common plane at right angles to said axis of relativerotation, and a plurality of sets of electrically connected scanningmembers for scanning the respective undulating rings inelectrostatically inductive relation, carried by the other part inanother common plane at right angles to said axis of relative rotationand at substantially the same radii as the respective rings, both theundulations and the scanning members of each inductively cooperatingring and set of scanning members being repeated about the axis ofrelative rotation at such intervals that, at any given moment, theundulation and the scanning member of every inductively operating pairare at the same relation.

8. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts, a plurality of electrodes electrically insulated from one anothercarried by one of said parts, each of which electrodes constitutes aplurality of wave forms, and a plurality of sets of scanning forms allelectrically connected to one another carried by the other part forscanning the respective wave form electrodes in inductive relationtherewith, both the wave and scanning forms of each inductivelycooperating wave form electrode and scanning form set being repeatedabout the axis of relative rotation at such intervals that, at any givenmoment, the wave form and scanning form of every inductively cooperatingpair are at the same relation.

9. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts, a plurality of rings of undulating form carried by one of saidparts in insulating relation to each other concentric with the axis ofrelative rotation and at different radii in a common plane at rightangles to said axis of relative rotation, and a plurality of sets ofscanning members, for scanning the respective undulating rings inelectrostatically inductive relation, carried by the other part inconductive relation to one another in another common plane at rightangles to said axis of relative rotation and at substantially the sameradii as the respective rings, both the undulations and the scanningmembers of each inductively cooperating ring and set of scanning membersbeing repeated about the axis of relative rotation at such intervalsthat, at any given moment, the undulation and the scanning member ofevery inductively cooperating pair are at the same relation.

10. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts having respective insulating surfaces in proximity to each other,a plurality of electrodes constituted by separated portions of a thinmetallic layer on one of said surfaces, each of which electrodesconstitutes a plurality of wave forms, and a plurality of sets ofelectrically connected scanning forms constituted by a metallicsubstance in grooves on the other surface for scanning the respectivewave form electrodes in electrostatically inductive relation thereto,both the wave and scanning forms of each inductively cooperating waveform electrode and scanning form set being repeated about the axis ofrelative rotation at such intervals that, at any given moment, the waveform and scanning form of every inductively cooperating pair are at thesame relation.

11. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts having respective insulating surfaces at right angles to the axisof relative rotation and in proximity to one another, a plurality ofrings of undulating form concentric with the axis of rotation andconstituted by divided portions of a thin metallic layer on one of saidsurfaces and a plurality of sets of electrically connected scanningmembers for the respective rings constituted by a metallic substance ingrooves in the other surface, both the undulations and the scanningmembers of each inductively cooperating ring and set of scanning membersbeing repeated about the axis of relative rotation at such intervalsthat, at any given moment, the undulation and the scanning member ofevery inductively cooperating pair are at the same relation.

12. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts having respective insulating surfaces in proximity to each other,a

plurality of electrodes in insulated relation to one another constitutedby separated portions of a thin metallic layer on one of said surfaces,each of which electrodes constitutes a plurality of wave forms, and aplurality of sets of scanning forms all in conductive relation to oneanother constituted by a metallic substance in grooves on the othersurface for scanning the respective wave form electrodes inelectrostatically inductive relation thereto, both the wave and scanningforms of each inductively cooperating wave form elec- 'trode andscanning form set being repeated about the axis of relative rotation atsuch intervals that, at any given moment, the wave form and scanningform of every inductively cooperating pair are at the same relation.

13. In an electrical musical instrument, an

electrostatic generator unit adapted to electrostatically induce varyingpotentials for producing a plurality of individual sound tones,comprising lated relation to one another concentric with the .axis ofrotationand constituted by divided portions of a thin metallic layer onone oi said surfaces, anda plurality of sets of scanning members for therespective rings all in conductive relation to one another constitutedby a metallic substance in grooves in the other surface, both theundulations and the scanning members of each inductively cooperatingring and set of scanning members being repeated about the axis ofrelative rotation at such intervals that, at any given moment, theundulation and the scanning member of every inductively cooperating pairare at the same relation.

14. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts having respective insulating surfaces at right angles to the axisof relative rotation and in proximity to one another, a plurality ofrings of undulating form in insulated relation to one another concentricwith the axis of rotation and constituted by divided portions of a thinmetallic layer on one of said surfaces, and a plurality of sets ofscanning members for the respective rings constituted by a metallicsubstance in grooves in the other surface and all in conductive relationto one another by virtue of extending between concentric conductingrings also constituted by a metallic substance in grooves in the othersurface, both the undulations and the scanning members of eachinductively cooperating ring and set of scanning members being repeatedabout the axis of relative rotation at such intervals that, at any givenmoment, the undulation and the scanning member of every inductivelycooperating pair are at the same relation.

15. In an electrical musical instrument, an electrostatic generator unitadapted to electrostatically induce varying potentials for producing aplurality of individual sound tones, comprising two relatively rotatableparts having respective insulating surfaces at right angles to the axisof relative rotation and in proximity to one another, a plurality ofrings of undulating form in insulated relation to one another concentricwith the axis of relative rotation and constituted, together withintermediate permanently earthed ring portions, by dividing a thinmetallic layer on one of said surfaces, and a plurality of sets ofscanning members for the respective rings all in conductive relation toone another constituted by a metallic substance in grooves in the othersurface, both the undulations and the scanning members of eachinductively cooperating ringandsetofscanningmembersbeingrepeated aboutthe axis of relative rotation at such intervals that, at any givenmoment, the undulation and the scanning member of every inductivelycooperating pair are at the same relation.

LEI-II EDWIN ALEXANDER HOUR-N.

